Art. 16. When, on the outbreak or in the course of hostilities, a locality is declared to be an "open town" the adverse Party shall be duly notified. The latter is bound to reply, and if it agrees to recognize the locality in question as an open town, shall cease from all attacks on the said town, and refrain from any military operation the sole object of which is its occupation. In the absence of any special conditions which may, in any particular case, be agreed upon with the adverse Party, a locality, in order to be declared an "open town," must satisfy the following conditions:

(a) it must not be defended or contain any armed force; (b) it must discontinue all relations with any nation or allied armed forces; (c) it must stop all activities of a military nature or for a military purpose in those of its installations or industries which might be regarded as military objectives; (d) it must stop all military transit through the town. The adverse Party may make the recognition of the status of "open town" conditional upon verification of the fulfilment of the conditions stipulated above. All attacks shall be suspended during the institution and operation of the investigatory measures.

The presence in the locality of civil defence services, or of the services responsible for maintaining public order, shall not be considered as contrary to the conditions laid down in paragraph 2. If the locality is situated in occupied territory, this provision applies also to the military occupation forces essential for the maintenance of public law and order. When an "open town" passes into other hands, the new authorities are bound, if they cannot maintain its status, to inform the civilian population accordingly. None of the above provisions shall be interpreted in such a manner as to diminish the protection which the civilian population should enjoy by virtue of the other provisions of the present rules, even when not living in localities recognized as "open towns."